Chapter Summaries

Yotsuba Mahiro battled Gada Qucokan at the docks, recovering from her attacks before overpowering her with close-combat techniques and freezing the sea against her Beast Vassal. As Gada fled, Mahiro activated Material Burst with Sakuradite and aimed it at her.

• Gada Qucokan broke Mahiro's arm with a kick, but he healed quickly and threw her through a warehouse.
• Mahiro used acceleration and his Tendo Style techniques to punch Gada across the sea and smash her beneath the waves.
• Gada summoned the Chaos Empress, Xiuhtecuhtli, and attacked Mahiro with a torrent of flames.
• Mahiro used Ice Fog Domain (Niflheimr) to freeze the flames, the sea, and the surrounding area.
• Gada fled with a spatial-movement Familiar, but Mahiro activated Material Burst on Sakuradite, prompting her to shout, "Xolotl!"

Yotsuba Mahiro defeated the Third Primogenitor and confronted the Feast of the Flame’s supervisor, while the Lion King Agency’s Three Saints learned that he had gathered all twelve vessels and killed the First Primogenitor. Koyomi Himgari recounted how Nagisa Akatsuki transformed after Mahiro fulfilled his agreement with the First Primogenitor.

• Mahiro’s attack left a vast trench in the sea, but the Third Primogenitor escaped, and he returned toward Itogami Island.
• Natsuki Minamiya declined to intervene as Koyomi Himgari faced Mahiro, who beat her despite her apology and offer of compensation.
• At High God Shrine, Yuantang Yuan wanted revenge, but An Shiranui and Koyomi Himgari persuaded her that the Lion King Agency could not match Mahiro’s power.
• Koyomi Himgari told Yuantang Yuan and An Shiranui that the Feast of the Flame ended without the Fourth Primogenitor appearing, as Mahiro gathered all twelve vessels and killed the First Primogenitor.
• Koyomi Himgari explained that the First Primogenitor had hidden inside Nagisa Akatsuki, who transformed after approaching the twelve vessels and praised Mahiro for fulfilling their agreement.

Mahiro betrayed the First Primogenitor during the Fourth Primogenitor’s awakening ritual and froze her soul, then settled into a new villa with the prototypes. Veldiana joined Avrora’s followers and was forced by Natsuki and Mahiro to become a maid, while the Three Saints agreed to wait another two and a half years.

• The First Primogenitor began transferring her soul into Avrora so she could awaken the Fourth Primogenitor, but Mahiro changed his mind and froze her soul with Lamenting Styx.
• Koyomi Himgari recounted Mahiro’s soul-targeting magic to Yuantang Yuan and An Shiranui, and the Three Saints agreed to wait two and a half years.
• Veldiana accepted Avrora as her lady and was told she would serve Natsuki as a maid in exchange for staying with the household.
• Mahiro and the eleven other prototypes moved into a villa Gamma had purchased, where Mahiro tore Veldiana’s clothes and made her put on a maid uniform.
• As Mahiro admired Veldiana in the uniform, someone covered his eyes and told him not to stare at a girl’s body.

After the Feast of the Flame, Mahiro lived with Nagisa and the others at the villa, where Veldiana served as head maid and the household settled into a lively routine. Two and a half years later, Nagisa still got Mahiro out of bed for school, while the morning ended with her catching her mother Misaki wearing Mahiro’s shirt and forcing her to change.

• The girls dressed Veldiana in a maid outfit and debated what clothes Mahiro preferred, while Natsuki called him a womanizer and fled after he invited her to bathe with him.
• Two and a half years after the Feast of the Flame, Nagisa woke Mahiro and supervised his morning routine so he would go to school.
• Mahiro ate breakfast with the crowded household, including the Flame Haze Night Emperors and Veldiana, who had become head maid.
• Yuuma suggested Mahiro skip school and rest, but he said Nagisa would scold him if he did.
• Misaki arrived in Mahiro’s shirt after staying up all night, and Nagisa caught her and pushed her away to change clothes.

After settling into school and family life following the Feast of the Flame, Mahiro encountered the Lion King Agency’s long-awaited move: Yukina Himeragi was assigned a dangerous mission involving him. Yukina received the weapon Schneewaltzer and prepared to approach Mahiro, though the Three Saints feared their plan might fail.

• Misaki Akatsuki caused morning chaos at home, and Nagisa Akatsuki scolded her for making a mess.
• Mahiro teleported to school with Est and Aye, where he saw Asagi Aiba, Yuuma, Kojou Akatsuki, and Motoki Yaze.
• The Lion King Agency’s Three Saints tested Yukina Himeragi’s abilities by attacking her with shikigami, which she destroyed.
• Koyomi Himgari gave Yukina the Seventh-Type Assault Demon-Suppressing Machine Gun, Schneewaltzer, and ordered her to master it for an unprecedentedly dangerous mission.
• Koyomi Himgari hoped Yukina could use her charm to win Mahiro over, while doubting whether the plan would succeed.

Yukina Himeragi passed her Sword Shaman training and was ordered by the Lion King Agency’s Three Sages to monitor Yotsuba Mahiro, whom they said controlled the Fourth Primogenitor’s twelve familiars. At Saikai Academy, Mahiro teased Asagi Aiba after discovering she had started menstruating.

• The Three Sages told Yukina Himeragi she had passed her training and showed her a photograph of Yotsuba Mahiro.
• Koyomi Himgari asked Yukina what she thought of Mahiro, then explained that the Fourth Primogenitor had not appeared after the Feast of the Flame and that its twelve familiars were under a man's control.
• Yuantang Yuan ordered Yukina to transfer to Saikai Academy, monitor Mahiro, and eliminate him if she found him dangerous.
• At school, Mahiro noticed that Asagi Aiba looked tired and heard Yuuma Sengakuji tease her about her period.
• Mahiro used the Eidos Eye to figure out what was going on and teased Asagi, who angrily told him to get lost.

Yotsuba Mahiro discovered that Yukina Himeragi had been sent by the Lion King Agency to monitor him and tricked her into waiting outside an empty restroom. After Yukina confronted him following the schoolwide gossip about her, Mahiro walked away, and she chased him into the boys’ restroom.

• Mahiro noticed Yukina Himeragi following him around campus and recognized her as the Lion King Agency’s new observer.
• Mahiro hid in a restroom stall, leaving Yukina waiting outside until she went in and found it empty.
• Mahiro laughed about Yukina’s humiliation, while rumors about her lurking by the boys’ restroom spread throughout Saikai Academy.
• Yukina confronted Mahiro after school, but he teased her and walked away before she could introduce herself.
• Yukina followed Mahiro into the boys’ restroom and demanded to know if he was trying to escape her again.

Yukina Himeragi confronted Yotsuba Mahiro in the school restroom and revealed that the Lion King Agency had sent her to monitor him. After Mahiro provoked her doubts and pulled her into a stall to hide from approaching students, Yukina challenged him with Schneewaltzer, but he stopped her attack effortlessly.

• Yukina told Mahiro that the Lion King Agency had sent her to monitor him because he could control the Fourth Primogenitor.
• Mahiro questioned whether the agency had truly sent Yukina to watch him, planting doubt despite her accusing him of trying to bewitch her.
• After Yukina's shout drew students toward the boys' restroom, Mahiro pulled her into a stall and covered her mouth until they left.
• Yukina emerged and aimed Schneewaltzer at Mahiro, who dismissed her skills and pinned her spear beneath his foot.
• Yukina freed Schneewaltzer, backed away, and began chanting a prayer that transformed the spear for a divine vibration-wave driving ritual.

Mahiro defeated Yukina and destroyed Schneewaltzer, then confronted Koyomi Himgari, the Lion King Agency observer known as Scarlet Rice. He brought her to a shopping street and offered a deal to protect the Agency, while warning that it could be gone by dawn if she left.

• Mahiro struck Yukina through Schneewaltzer, breaking the weapon and leaving her humiliated and in pain.
• Mahiro went to Motoki Yaze's apartment and asked Scarlet Rice to come talk with him; she agreed and left with him.
• Mahiro revealed that he knew Scarlet Rice was Koyomi Himgari, head of the Three Saints and an observer assigned to monitor him.
• Mahiro led Koyomi through a park and shopping street, then asked why she had been at Motoki Yaze's apartment.
• When Koyomi gathered cursed power and challenged him, Mahiro snapped his fingers and made it dissipate.
• Mahiro said he wanted her to walk with him and offered a deal to ensure the Lion King Agency's safety, while warning it might not survive until dawn if she left.

Yotsuba Mahiro confronted Scarlet Rice, exposed her identity as Koyomi Himgari, and forced her to reveal her relationship with Motoki Yaze. He kissed and assaulted her in the alley while angrily rebuking the Lion King Agency, leaving her trapped and humiliated.

• Yotsuba Mahiro questioned Scarlet Rice about dating Motoki Yaze and dragged her into a dark alley.
• Mahiro removed Scarlet Rice’s disguise, recognized her as Koyomi Himgari, and pinned her against the wall.
• Koyomi admitted that she and Motoki were romantically involved and explained that his family and ties to the Artificial Island Management Corporation made him useful to the Lion King Agency.
• Mahiro pressed Koyomi about how far their relationship had gone, then kissed her when she would not answer.
• Mahiro restrained Koyomi and repeatedly spanked her while berating the Lion King Agency for sending people to monitor and manipulate him.

After failing her mission and damaging Schneewaltzer, Yukina Himeragi feared the Lion King Agency would recall and punish her. She received the repaired spear and a summons to its Itogami Island office, where she reunited with her master, who appeared as a black cat.

• Yukina stayed home for three days, overwhelmed by her mission failure and the loss of Schneewaltzer.
• A delivery left Yukina a case containing a repaired Schneewaltzer and a letter ordering her to go alone to the Lion King Agency's Itogami Island office.
• Yukina prepared herself and went to the Agency's disguised office in an antique shop.
• A shikigami resembling Sayaka Kirasaka greeted Yukina and led her to her master, who appeared as a black cat.
• Yukina knelt before her master, and the black cat observed that she had already cried.

Yukina Himeragi learned from her master that the Lion King Agency’s rumors were true and that its pursuit of peace involved compromises. Meanwhile, Koyomi Himgari suffered the effects of Mahiro’s actions, and Natsuki Minamiya recruited Mahiro to investigate strange murders involving demonkind on Itogami Island.

• Yukina Himeragi admitted that Yotsuba Mahiro had told her about the Lion King Agency’s rumors, and her master confirmed they were true.
• Yukina’s master explained that the Lion King Agency paid a price to maintain peace and revealed that Koyomi Himgari was suffering but was not in mortal danger.
• Koyomi Himgari, using the alias Scarlet Rice, endured a strange physical sensation at school and left for the infirmary.
• Natsuki Minamiya invited Mahiro for tea, then asked him to help investigate recent murders involving demonkind on Itogami Island.

Yotsuba Mahiro investigated the murders of three demonkin at Itogami Island’s eastern port and identified the likely culprit as Rudolf Eustach, an anti-priest from Lotharingia. He took charge of the case and told Beta not to intervene, intending to confront Rudolf himself because the island had taken a saint’s arm to power its core.

• Misaki Sasaki reported that three demonkin had been drained of their magic before they were beheaded and their hearts pierced.
• Yotsuba Mahiro examined the warehouse and identified the marks on the floor as those of a European long-handled battle axe.
• Mahiro urged Natsuki Minamiya to leave the investigation to him, and she agreed despite Misaki’s concern about the security force’s authority.
• Beta appeared beside Mahiro and offered to deal with the culprit, but he refused and said he would handle the matter himself.
• Mahiro revealed that he understood Rudolf Eustach’s motive for seeking the saint’s arm and had already formed a plan.

Yotsuba Mahiro, Alpha, and a silver-haired girl confronted Rudolf Eustach after he and Astarte defeated two demons. Mahiro offered to help Rudolf recover the Saint’s right arm, and Rudolf asked what he wanted in return.

• Rudolf Eustach and Astarte lured two demons into a fight, and Rudolf severely wounded the beastman with his battle axe.
• The vampire attacked Rudolf with his Familiar, but Astarte blocked it and used Rose’s Fingertips to destroy it and drain the demons’ magic power.
• Rudolf identified himself as a Heretic Slayer of Lotharingia and told Astarte to show the defeated demons mercy, which she did by absorbing their magic power.
• Yotsuba Mahiro arrived with Alpha and a silver-haired girl, introduced himself as an externally contracted attack mage for Itogami Island, and said he had come to find Rudolf.
• Mahiro offered to help Rudolf reclaim the Saint’s right arm, and Rudolf asked what Mahiro wanted in exchange.

Yotsuba Mahiro offered Rudolf a chance to reclaim the Saint’s Right Arm in exchange for Astarte, then met Yukina Himeragi while leaving to see Rudolf after the three-day deadline. He kissed Yukina and insisted she accompany him once she had dried off and changed.

• Yotsuba Mahiro offered to help Rudolf reclaim the Saint’s Right Arm if Rudolf gave him Astarte, and gave him three days to decide while forbidding him from killing demons.
• Rudolf questioned why Yotsuba Mahiro would risk bringing catastrophe to the artificial island, and Mahiro said he disliked the Artificial Island Management Corporation.
• After three days passed, Yotsuba Mahiro left home to meet Rudolf and ran into Yukina Himeragi, who had rushed over from her bath to monitor him.
• Yotsuba Mahiro teased Yukina about her damp clothes, kissed her, and stopped her from calling the police by threatening consequences for the Lion King Agency.
• Yotsuba Mahiro told Yukina to dry herself and change clothes, then said he would wait for her so they could leave together.

Yotsuba Mahiro brought Yukina to an abandoned Lotharingian laboratory, where they found artificial lifeforms and encountered Astarte and Rudolf. Astarte warned that Itogami Island would soon sink, while Mahiro negotiated with Rudolf to reclaim the immortal treasure in exchange for Astarte.

• Mahiro teased Yukina before taking her to an abandoned research facility in the northern district of Itogami Island.
• Mahiro dispelled an illusion at the entrance and led Yukina into a laboratory filled with tanks holding artificial lifeforms.
• Mahiro used Nihility to shatter the cultivation tanks, then continued with Yukina toward the facility's largest vessel.
• Yukina confronted Astarte, who warned them that Itogami Island would soon sink and urged them to escape.
• Mahiro stopped Yukina from attacking Astarte and asked where her Church Slayer was, prompting Rudolf to appear.
• Mahiro offered to help Rudolf reclaim the immortal treasure in return for Rudolf handing Astarte over to him.

Yotsuba Mahiro, Rudolf Eustach, and their companions broke into the Keystone Gate to seize the sacred relic anchoring Itogami Island, while Yukina Himeragi struggled with the danger to the island’s inhabitants. They reached the lowest level and found the Keystone containing the arm of a saint.

• Rudolf agreed to cooperate with Mahiro, while Mahiro reminded Yukina that she was a monitor, not his guardian.
• Astarte tore through the Keystone Gate’s armored wall, and Yukina realized the group intended to remove the relic that anchored Itogami Island.
• Mahiro used Est’s CAD to erase the doors blocking their way, alarming Rudolf and Yukina with the weapon’s power.
• Asagi Aiba and Mogwai failed to regain access to the Keystone Gate’s surveillance feeds while the intruders descended and knocked out guards.
• Mahiro led the group to the lowest level, where they found the Keystone and the mummified arm within it.

Yotsuba Mahiro retrieved the saint’s arm for Rudolf and replaced it with his Alpha Stigma eye to keep Itogami Island stable, then healed his eye. Natsuki Minamiya arrived and examined the new keystone.

• Eustach ordered Astarte to remove the saint’s arm and destroy Itogami Island, but Mahiro stopped her and refused to break their agreement.
• Mahiro used Spatial Transfer to take the saint’s arm from the keystone and placed his Alpha Stigma eye inside it to stabilize the island.
• Mahiro healed his damaged eye with Regrowth, while Yukina reacted with shock and worried about the earthquake and the report she would have to write.
• Mahiro gave Rudolf the saint’s arm, and Rudolf thanked him before leaving the Keystone Gate.
• Natsuki Minamiya appeared, scolded Mahiro for causing trouble, and looked at his eye inside the keystone.

Natsuki learned that Itogami Island was a sacrificial altar built to resurrect Cain, while Mahiro supported her decision about what to do. After the island’s earthquake was publicly explained away and the Saint’s Remains incident was suppressed, Yukina moved into the villa next to Mahiro’s, leaving him astonished at how little luggage she had.

• Natsuki told Mahiro she had discovered Itogami Island was Cain’s altar and learned that its residents were meant to be sacrificed to resurrect him.
• Mahiro encouraged Natsuki to follow her heart, and Yukina accidentally overheard their conversation.
• The Artificial Island Management Corporation blamed the earthquake on an ordinary tremor, dropped the matter of the Saint’s Remains, and Rudolf secretly left Itogami Island.
• Astarte moved into the Yotsuba Estate, while Avrora watched Mahiro from the villa balcony and wondered if she could help him.
• Yukina told Mahiro that the Lion King Agency had arranged for her to move into the neighboring villa so she could monitor him.
• Yukina’s moving truck arrived with only three medium-sized boxes, and Mahiro asked if that was all her luggage.

Mahiro helped Yukina move into her villa, then took her shopping for household goods and discovered her alarming tendency to imagine ordinary products as weapons. The chapter ended with Yuantang Yuan and An Shiranui consulting Koyomi Himgari’s shikigami about Mahiro while Koyomi remained afflicted by a mysterious condition.

• Yukina asked Mahiro to help move her belongings, and he accidentally opened a box of her underwear before offering to help furnish her empty villa.
• Mahiro took Yukina to a department store, where she treated ordinary goods as dangerous weapons and asked whether cleaning products could be used to kill someone without a trace.
• Yukina bought three cartloads of household goods for nearly three million yen using the Lion King Agency’s allowance, and Mahiro recognized the store as belonging to his family’s Four Crossing Trading Company.
• Yuantang Yuan and An Shiranui spoke with Koyomi Himgari’s shikigami crow about Mahiro’s power and Yukina’s growing closeness to him.
• Yuantang Yuan learned that Koyomi remained under a mysterious curse that kept her away from school and her boyfriend, Motoki Yaze.